The aim of this study is to examine, in a longitudinal design, the causal patterns among stressors, social support and illness (physical and psychiatric disturbances). The study is designed to collect data in two waves from the same respondents in a representative sample of the normal population in the Tri-City area (Albany-Schenectady-Troy, New York). The first wave was collected in the Spring of 1979. The present investigation provides for a one-year follow-up (Spring 1980). Specifically we are examining, causally, the potential intervening effect of social support on the relationship between stressors and illness. Two major research questions under examination are the extent to which stressors present in time 1 will affect illness in time 2. Further, the history of illness, sociodemographic variables, and a measure of internal control will be taken into account in an examination of these relationships. This elaboration would allow an investigation into the contributions of stressors and social support to illness relative to other causal (instrumental) variables.